Heat resistant aerogel materials

Abstract

The present disclosure provides an aerogel composition which is durable and easy to handle, which has favorable performance in aqueous environments, and which also has favorable combustion and self-heating properties. Also provided is a method of preparing an aerogel composition which is durable and easy to handle, which has favorable performance in aqueous environments, and which has favorable combustion and self-heating properties. Further provided is a method of improving the hydrophobicity, the liquid water uptake, the heat of combustion, or the onset of thermal decomposition temperature of an aerogel composition.

What is claimed is: 
     
         1 . A method for preparing a reinforced aerogel composite, comprising:
 providing a reinforced aerogel composition comprising a silica-based aerogel framework, a reinforcement material, and hydrophobic organic material; and   exposing the reinforced aerogel composition to a heat treatment in a reduced oxygen atmosphere to form a hydrophobic reinforced, silica-based aerogel composite, wherein the heat treatment comprises exposure to one or more temperatures above 300° C. and below 850° C., for a total duration of between 30 seconds and 200 minutes,   wherein the reinforced aerogel composition is not exposed to a temperature above 700° C. for more than 1 minute.   
     
     
         2 . The method of  claim 1 , wherein the total duration of the heat treatment is between 1 minute and 60 minutes. 
     
     
         3 . The method of  claim 1 , wherein the total duration of the heat treatment is between 1 minute and 10 minutes. 
     
     
         4 . The method of  claim 1 , wherein the reinforcement material comprises fibers. 
     
     
         5 . The method of  claim 1 , wherein the reduced oxygen atmosphere is about 85% inert gas by volume. 
     
     
         6 . The method of  claim 1 , wherein the reduced oxygen atmosphere is 0.01% to 10% oxygen by volume. 
     
     
         7 . The method of  claim 1 , wherein the hydrophobic organic material before the heat treatment includes at least 50% aliphatic hydrophobic groups. 
     
     
         8 . The method of  claim 1 , wherein:
 the hydrophobic organic material before the heat treatment includes methyl hydrophobic groups; and   the methyl hydrophobic groups comprise at least 50% of the hydrophobic organic material.   
     
     
         9 . A hydrophobic reinforced, silica-based aerogel composite produced by the method of  claim 1 . 
     
     
         10 . The hydrophobic reinforced, silica-based aerogel composite of  claim 9 , wherein the hydrophobic reinforced, silica-based aerogel composite has an onset of thermal decomposition of the hydrophobic organic material between 525° C. and 635° C. 
     
     
         11 . The hydrophobic reinforced, silica-based aerogel composite of  claim 9 , wherein the hydrophobic reinforced, silica-based aerogel composite has an onset of thermal decomposition of the hydrophobic organic material of greater than 525° C. 
     
     
         12 . A method for preparing a reinforced aerogel composite, comprising:
 providing a reinforced aerogel composition comprising a silica-based aerogel framework, a reinforcement material, and hydrophobic organic material; and   exposing the reinforced aerogel composition to a heat treatment in an inert atmosphere between 85 vol. % and 99.9 vol. % inert gas to form a hydrophobic reinforced, silica-based aerogel composite, wherein the heat treatment comprises exposure to one or more temperatures between 200° C. and below 800° C., for a total duration of between 1 minute and 3 hours,   wherein the reinforced aerogel composition is not exposed to a temperature above 700° C. for more than 1 minute.   
     
     
         13 . The method of  claim 12 , wherein the total duration of the heat treatment is between 1 minute and 60 minutes. 
     
     
         14 . The method of  claim 12 , wherein the total duration of the heat treatment is between 1 minute and 10 minutes. 
     
     
         15 . The method of  claim 12 , wherein the reinforcement material comprises fibers. 
     
     
         16 . The method of  claim 12 , wherein the inert atmosphere is 0.01% to 10% oxygen by volume. 
     
     
         17 . The method of  claim 12 , wherein the hydrophobic organic material before the heat treatment includes at least 50% aliphatic hydrophobic groups. 
     
     
         18 . The method of  claim 12 , wherein:
 the hydrophobic organic material before the heat treatment includes methyl hydrophobic groups; and   the methyl hydrophobic groups comprise at least 50% of the hydrophobic organic material.